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471.
本文根据组合模式原理提出了一种用小震调制比(rm)异常区出现高频次的空间异常图,进行强地震中短期预报的方法,简称rs法。该方法在预报强震地点和时间上可望取得较好效果。本文在介绍该方法的基础上,应用该法对3次7级以上大震进行了回顾性检验。 相似文献
472.
473.
Phosphorous (P) fraction characteristics in sediment resuspension were investigated under adequately hydrodynamic conditions.
Four forms of P in overlying water, including dissolved inorganic P, dissolved total P, total P, and particulate P, and six fractions of
P in suspended particulate matter (SPM), including loosely sorbed P (NH4Cl-P), redox-sensitive P (BD-P), aluminum-bound P (Al-
P), organic P (NaOH-nrP), calcium-bound P (Ca-P) and residual P (Res-P), were quantified, respectively. Di erent hydrodynamic
conditions resulted in di erent P form changes. Four states could be ascribed: (1) P desorption by sediment and SPM, and P adsorption
by overlying water; (2) P desorption by SPM, and P adsorption by overlying water; (3) P adsorption by SPM, and P desorption by
overlying water; and (4) P equilibrium between SPM and overlying water. The contents of P in overlying water acquired peak values
in the middle position of the vertical P distribution due to the combined actions of SPM and sediment. P fractions in SPM were in the
following order: BD-P > NaOH-nrp > Ca-P > Al-P > Res-P > NH4Cl-P. BD-P in SPM frequently exchanged with P forms in overlying
water. Resuspension was favorable to forming Ca-P in SPM. 相似文献
474.
采用危险与可操作性(HAZOP)分析方法,对某个GE水煤浆装置的气化炉烧嘴进行了分析,识别出了烧嘴监测和进料控制中存在的问题。烧嘴监测中存在的问题主要是CO浓度监测和烧嘴压差监测不准;烧嘴进料控制中存在的问题主要是煤浆的流量,浓度测量和氧气的流量测量存在缺陷。针对HAZOP识别出的烧嘴监控问题,提出了改进的措施。 相似文献
475.
随着科学技术的不断发展和社会的进步,防盗报警监控系统正越来越多地被应用于各个领域。输油站库是一个重点防范单位,特别是大型油库,为了更好地管理,有效防止非法入侵及油库的安全,建立一套周界安全防范监控报警系统是非常必要的。 相似文献
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479.
实施HAZOP分析控制重大工艺安全事故(Ⅰ) 总被引:3,自引:2,他引:1
介绍了危险与可操作性分析(Hazard and Operability,HAZOP)技术的国内外应用现状。结合我国重大工艺安全事故案例,阐述了在我国实施HAZOP的必要性。 相似文献
480.
Pb(II) biosorption using chitosan and chitosan derivatives beads: Equilibrium, ion exchange and mechanism studies 总被引:2,自引:2,他引:0
The study examined the adsorption of Pb(II) ions from aqueous solution onto chitosan, chitosan-GLA and chitosan-alginate beads.
Several important parameters influencing the adsorption of Pb(II) ions such as initial pH, adsorbent dosage and di erent initial
concentration of Pb(II) ions were evaluated. The mechanism involved during the adsorption process was explored based on ion
exchange study and using spectroscopic techniques. The adsorption capacities obtained based on non–linear Langmuir isotherm for
chitosan, chitosan-GLA and chitosan-alginate beads in single metal system were 34.98, 14.24 and 60.27 mg/g, respectively. However,
the adsorption capacity of Pb(II) ions were reduced in the binary metal system due to the competitive adsorption between Pb(II) and
Cu(II) ions. Based on the ion exchange study, the release of Ca2+, Mg2+, K+ and Na+ ions played an important role in the adsorption
of Pb(II) ions by all three adsorbents but only at lower concentrations of Pb(II) ions. Infrared spectra showed that the binding between
Pb(II) ions and the adsorbents involved mostly the nitrogen and oxygen atoms. All three adsorbents showed satisfactory adsorption
capacities and can be considered as an e cient adsorbent for the removal of Pb(II) ions from aqueous solutions. 相似文献